1. Field of the Invention
The present invention relates to paper feed trays furnished inside with a mechanism for lifting a paper stack, and to printers furnished with the tray.
2. Description of Related Art
Paper feed trays are installed in a printer for printing images or the like and feed paper sheets to the printer. There is a type of paper feed tray in which an auxiliary tray frame adapted for smaller-sized paper sheets is attachable to a tray unit adapted for larger-sized paper sheets.
An example of a conventional auxiliary tray frame 7 is shown in FIG. 11. In FIG. 11, the left side of the figure is the front. In this configuration, the rear ends of opposing side frame portions 73 and 74 are connected by a rear frame portion 72, and the fore-ends of the side frame portions 73 and 74 are free ends. The auxiliary tray frame 7 is mounted in a tray unit 1 so that the fore-ends of both side frame portion 73 and 74 face a front wall 11 of the tray unit 1. The front wall 11 of the tray unit 1 also serves as the front wall of the smaller-sized paper sheet tray.
In both cases of large-sized paper sheets and small-sized paper sheets, paper sheets are drawn out from the upper end of the front wall 11 of the tray unit 1 by a paper-feeding roller of the printer (not shown).
The above-noted paper feed tray has the following problem. The just-noted auxiliary tray frame 7 lacks one of the four sides that make up the frame. For this reason, the strength is small against an external force that acts on the side frame portions 73 and 74. In many cases the auxiliary tray frame 7 is formed of a synthetic resin and is apt to break when the external force acts thereon.
The present invention is to disclose a paper feed tray that can solve the foregoing problem.